/*
 * Javlov - a Java toolkit for reinforcement learning with multi-agent support.
 * 
 * Copyright (c) 2009 Matthijs Snel
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package net.javlov.policy;

import net.javlov.Option;
import net.javlov.Policy;
import net.javlov.State;

public abstract class AbstractPolicy implements Policy {

	protected Option currentOption;
	
	protected boolean interruptOptions = false;
	
	@Override
	public <T> Option getOption(State<T> s) {
		if ( currentOption == null || currentOption.isFinished() ) {
			currentOption = pickNewOption(s);
		}
		else if ( interruptOptions && interruptCurrentOption(s) ) {
			currentOption.setFinished();
			currentOption = pickNewOption(s);
		}
		return currentOption;
	}

	@Override
	public <T> Option getOption( State<T> s, double[] qvalues ) {
		if ( currentOption == null || currentOption.isFinished() ) {
			currentOption = pickNewOption(s, qvalues);
		}
		else if ( interruptOptions && interruptCurrentOption(s, qvalues) ) {
			currentOption.setFinished();
			currentOption = pickNewOption(s, qvalues);
		}
		return currentOption;
	}
	
	@Override
	public void init() {
		currentOption = null;
	}
	
	@Override
	public void reset() {
		currentOption = null;
	}
	
	public boolean interruptsOptions() {
		return interruptOptions;
	}

	public void setInterruptOptions(boolean interruptOptions) {
		this.interruptOptions = interruptOptions;
	}
	
	protected abstract <T> Option pickNewOption(State<T> s);
	
	protected abstract <T> Option pickNewOption(State<T> s, double[] qvalues);
	
	protected <T> boolean interruptCurrentOption(State<T> s) {
		return false;
	}
	
	protected <T> boolean interruptCurrentOption(State<T> s, double[] qvalues) {
		return false;
	}

}
